1. Field of the Invention
The present invention relates to integral fastening structures for holding together the top and bottom chassis of flat panel displays, and flat panel displays incorporating the same.
2. Related Art
Among flat panel displays, the application range of liquid crystal displays (LCDs) has been extended because of its light weight, thinness, low drive power requirements, full color capabilities and high resolution characteristics. LCDs are currently used in computers, notebook computers, PDAs, telephones, TVs, audio/video devices and the like. Such LCD panels are used to modulate light transmitted by the panels in accordance with image signals applied to control switches arrayed in a matrix therein and then display a desired image on a surface of the display. The LCD device comprises an LCD panel having a surface on which images are displayed directly, an LCD drive IC for operating the LCD panel, a backlight unit used as a light source of the LCD, and a chassis used to fasten respective components of the LCD into a single, integrated panel unit.
Recently, two features have emerged as being of major interest to users of medium- or small-sized LCDs, viz., a high luminance and a reduced thickness. The latter feature is one of particular importance to manufacturers of host devices that incorporate LCD panels, and accordingly, a variety of fastening structures have been developed with a view towards reducing panel thickness. Among the various prior art fastening structures that have been developed, the most commonly employed structure is one in which a flange-shaped fastening portion is formed on a module of an LCD that is to be incorporated in the host device, as illustrated in FIG. 1.
FIG. 1 is a perspective view of a generic LCD. With referring to FIG. 1, the LCD comprises an LCD panel 10, a mold frame 20 in which the LCD panel 10 is received, and a bottom chassis 30 that is fastened to the mold frame 20. A flange-shaped fastening portion 25 is formed on a side surface of the mold frame 20 and is used to fasten the LCD to a host device.
FIGS. 2A and 2B are upper front perspective and side elevation views, respectively, of an LCD incorporating dual liquid crystal panels in accordance with the prior art. Referring to FIGS. 2A and 2B, the LCD comprises a sub-side LCD panel 10, a mold frame 20 for accommodating a backlight unit therein, and a bottom chassis 30 fastened to the mold frame 20. Additionally, a flange-shaped fastening portion 25 is formed on a side surface of the mold frame 20 for fastening the LCD to a host device. The sub-side LCD panel 10 is disposed on an outer side of the bottom chassis 30, and a main-side LCD panel (not illustrated) is disposed on an opposite side of the mold frame 20.
FIGS. 3A and 3B are enlarged plan and cross-sectional views, respectively, of the regions encircled by phantom lines in FIGS. 1 and 2B, showing corresponding portions of the LCD mold frame 20 and bottom chassis 30 at which the chassis portions are fastened together in accordance with the prior art fastening structure. Referring to these figures, a hook 23, which protrudes a selected distance outward, is formed on a side surface of the mold frame 20. A coupling opening 35 corresponding to the shape and location of the hook 23 is formed in a sidewall of the bottom chassis 30, together with a rectangular hook fixing portion 33, which tapers inwardly from the sidewall of the bottom chassis. The resilient material of the mold frame and chassis enable the two fastening portions to be pressed together in an over-center, snap-in locking engagement with each other to fasten the two parts together.
In the prior art fastening structure described above, flange-shaped fastening portions are formed on a side surface of the mold frame for fastening the panel to the host device. However, as will be appreciated, there are many constraints on the design of the side surfaces of an LCD. In particular, the space needed for the hooks used to fasten the bottom chassis to the top chassis is insufficient due to the presence of the flange-shaped fastening portions. As a result, the size and/or number of the hooks must be decreased, and hence, the strength of the joints that fasten the top and bottom chassis together is correspondingly reduced. This, in turn, substantially reduces the ability of the LCD panel to withstand external shocks and impacts acting on the panel.